While we believe a healthy society is one in which members contribute to the general well-being, there is little research or theory regarding the development of citizenship. The purpose of this project is to provide data that characterizes citizenship attitudes and behaviors in adolescence and young adulthood, and identifies antecedent child, family, and environmental factors that contribute to the expression of citizenship. Existing research on prosocial development tends to be retrospective and focused on laboratory-based or simple situations. This project involves a long-term prospective study that is designed to better our understanding of naturally occurring prosocial behavior and the factors that relate to such behavior. Subjects have participated in a longitudinal study of social, cognitive, and behavioral development from infancy through 18 years. At 18 years, data were collected on subjects' volunteer activities, prosocial reasoning, and their altruistic attitudes, which were hypothesized to represent multiple facets of citizenship. Further, it is hypothesized that antecedent factors will differentially predict aspects of citizenship. Work to date has shown that citizenship is not necessarily a unitary concept. This suggests that there may be different developmental pathways for volunteering, altruism, and reasoning, which this proposal is designed to study. The first of two studies described in this proposal is designed to examine the development of citizenship, determining the effects of individual, family, and environmental factors on volunteering, altruism, and reasoning. In addition to examining citizenship at a particular time, it is necessary to determine how citizenship changes. In the second study described in this proposal, citizenship information will be collected from subjects when they are young adults. This way, we can determine whether individuals change their attitudes and behaviors as they transition into adulthood. Furthermore, we will be able to determine whether antecedent events are related to those changes. The following are the specific goals of this proposal: 1) to determine antecedent individual, family, and environmental factors of citizenship at 18 and 21 years of age; and 2) to determine the ways citizenship changes from adolescence through adulthood.